December 23, 2020. The xDai stable chain, an Ethereum compatible layer 2 sidechain, has completed a consensus upgrade to a delegated Proof-of-Stake architecture called POSDAO. The previous consensus model relied on a select group of validators to sign and order transactions. With POSDAO, public users who hold the STAKE governance token on the xDai chain can apply to become validators, and community members with less STAKE can also participate in the consensus process as delegators.